These below are nine year old recommendations by a club member, I personally haven't interfaced with these shops.
I'd recommend calling Lou Verdiales at Aero Dynamics (Phone #386-304-0380) in Daytona Beach. He'll definitely find and fix the problem with your 928 so you can be on your way home as soon as possible.
If you need another shop with good 928 skills and experience try Dan's Werkshop at 321-724-3059 in West Melbourne. It's a little further south, but they will fix your car as well.
Rich
Membership Chairman
Charter Member
1993 928 GTS Cover Girl
1987 928 S4
1979 928 5-speed rescue
1979 928 5-liter track beast